Marked variations in proximal colon cancer survival by race/ethnicity within the United States

American Indian/Alaska Native and black colon cancer patients have poorer cause-specific survival based on disease stage and anatomic site of diagnosis

OBJECTIVES

Studies of race-specific colon cancer (CC) survival differences between right- vs. left-sided CC typically focus on Black and White persons and often consider all CC stages as one group. To more completely examine potential racial and ethnic disparities in side- and stage-specific survival, we evaluated 5-year CC cause-specific survival probabilities for five racial/ethnic groups by anatomic site (right or left colon) and stage (local, regional, distant).

METHODS

We obtained cause-specific survival probability estimates from National Cancer Institute's population-based Surveillance, Epidemiology, and End Results (SEER) for CC patients grouped by five racial/ethnic groups (Non-Hispanic American Indian/Alaska Native [AIAN], Non-Hispanic Asian/Pacific Islander [API], Hispanic, Non-Hispanic Black [NHB], and Non-Hispanic White [NHW]), anatomic site, stage, and other patient and SEER registry characteristics. We used meta-regression approaches to identify factors that explained differences in cause-specific survival.

RESULTS

Diagnoses of distant-stage CC were more common among NHB and AIAN persons (>22 %) than among NHW and API persons (< 20 %). Large disparities in anatomic site-specific survival were not apparent. Those with right-sided distant-stage CC had a one-year cause-specific survival probability that was 16.4 % points lower (99 % CI: 12.2-20.6) than those with left-sided distant-stage CC; this difference decreased over follow-up. Cause-specific survival probabilities were highest for API, and lowest for NHB, persons, though these differences varied substantially by stage at diagnosis. AIAN persons with localized-stage CC, and NHB persons with regional- and distant-stage CC, had significantly lower survival probabilities across follow-up.

CONCLUSIONS

There are differences in CC presentation according to anatomic site and disease stage among patients of distinct racial and ethnic backgrounds. This, coupled with the reality that there are persistent survival disparities, with NHB and AIAN persons experiencing worse prognosis, suggests that there are social or structural determinants of these disparities. Further research is needed to confirm whether these CC cause-specific survival disparities are due to differences in risk factors, screening patterns, cancer treatment, or surveillance, in order to overcome the existing differences in outcome.

The rise of proximal colorectal cancer: a trend analysis of subsite specific primary colorectal cancer in the SEER database

Background

Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer-related deaths. Given the significant prevalence of CRC, regular preventative screening is required. CRCs in different locations of the colon have variable molecular pathogenesis, gross appearance, and general disease outcomes. While the overall incidence of CRC has been decreasing, the decrease in proximally located CRC significantly lags behind the other forms of CRC. The objective of this study was to establish independent risk factors for proximal CRC for better identification of populations at risk for closer CRC monitoring and observation.

Methods

A time-trend analysis was conducted using data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database from 1973-2007, comparing patient characteristics (age, sex, race/ethnicity, year of diagnosis, age of diagnosis, tumor grade, tumor stage, and urban-rural setting) between CRCs originating in different locations.

Results

Analysis demonstrated that black race, female sex, age over 60, and being diagnosed in the 21st century (rather than 20th) were associated with an increased risk of proximal CRC compared to CRCs originating in other locations.

Conclusions

Our study showed that black race, female sex, and age over 60 independently increased the likelihood of proximal CRC diagnosis. Furthermore, CRC trends identify an increasing proportion of all CRCs being of proximal origin. It is imperative that patients undergo regularly scheduled complete colonoscopies by trained endoscopists, especially if they belong to the high-risk groups previously identified.

Epidemiology of Colorectal Cancer and the Risk Factors in Kermanshah Province-Iran 2009-2014

INTRODUCTION AND OBJECTIVE

Colorectal cancer is the fourth prevalent cancer in the world and there are several factors effective on development of the disease. These factors vary based on geographical distribution. The present study is aimed at surveying epidemiology of colorectal cancer and its risk factors in Kermanshah-Iran between 2009 and 2014.

METHODOLOGY

A descriptive cross-sectional study was carried out on all colorectal cancer cases in two Kermanshah-based hospitals Imam Reza and Taleghani between 2009 and 2014. Demographic and epidemiological information was collected from the medical files and interviewing the patients. The collected data was analyzed in SPSS.

FINDINGS

Totally, 336 patients had been registered from 2009 to 2014. Mean and standard deviation of age was 59.98 ± 15.26. Fifty-four subjects (16.05%) had a history of colorectal cancer among their relatives and 253 (62.5) had no history of physical activity. In addition, 81 subjects (24.1%) had a history of digestive diseases. In terms of diet, 205 subjects (61%) used less than 6 unit/day of grains and bread, and meat consumption in 150 subjects (44.6%) was less than 2 unit/day.

CONCLUSION

The results showed that the prevalence of colorectal cancers was growing in Kermanshah. To change the rate, changes in lifestyle and screening tests for more susceptible age groups are recommended.

Improving Internal Medicine Residents' Colorectal Cancer Screening Knowledge Using a Smartphone App: Pilot Study

BACKGROUND

Colorectal cancer (CRC) is the third most common type of cancer and the second leading cause of cancer death in the United States. About one in three adults in the United States is not getting the CRC screening as recommended. Internal medicine residents are deficient in CRC screening knowledge.

OBJECTIVE

The objective of our study was to assess the improvement in internal medicine residents' CRC screening knowledge via a pilot approach using a smartphone app.

METHODS

We designed a questionnaire based on the CRC screening guidelines of the American Cancer Society, American College of Gastroenterology, and US Preventive Services Task Force. We emailed the questionnaire via a SurveyMonkey link to all the residents of an internal medicine department to assess their knowledge of CRC screening guidelines. Then we designed an educational intervention in the form of a smartphone app containing all the knowledge about the CRC screening guidelines. The residents were introduced to the app and asked to download it onto their smartphones. We repeated the survey to test for changes in the residents' knowledge after publication of the smartphone app and compared the responses with the previous survey. We applied the Pearson chi-square test and the Fisher exact test to look for statistical significance.

RESULTS

A total of 50 residents completed the first survey and 41 completed the second survey after publication of the app. Areas of CRC screening that showed statistically significant improvement (P<.05) were age at which CRC screening was started in African Americans, preventive tests being ordered first, identification of CRC screening tests, identification of preventive and detection methods, following up positive tests with colonoscopy, follow-up after colonoscopy findings, and CRC surveillance in diseases.

CONCLUSIONS

In this modern era of smartphones and gadgets, developing a smartphone-based app or educational tool is a novel idea and can help improve residents' knowledge about CRC screening.

Fusobacterium nucleatum in Colorectal Carcinoma Tissue According to Tumor Location

Objectives:

Evidence suggests a possible role of Fusobacterium nucleatum in colorectal carcinogenesis, especially in right-sided proximal colorectum. Considering a change in bowel contents and microbiome from proximal to distal colorectal segments, we hypothesized that the proportion of colorectal carcinoma enriched with F. nucleatum might gradually increase along the bowel subsites from rectum to cecum.

Methods:

A retrospective, cross-sectional analysis was conducted on 1,102 colon and rectal carcinomas in molecular pathological epidemiology databases of the Nurses’ Health Study and the Health Professionals Follow-up Study. We measured the amount of F. nucleatum DNA in colorectal tumor tissue using a quantitative PCR assay and equally dichotomized F. nucleatum-positive cases (high vs. low). We used multivariable logistic regression analysis to examine the relationship of a bowel subsite variable (rectum, rectosigmoid junction, sigmoid colon, descending colon, splenic flexure, transverse colon, hepatic flexure, ascending colon, and cecum) with the amount of F. nucleatum.

Results:

The proportion of F. nucleatum-high colorectal cancers gradually increased from rectal cancers (2.5% 4/157) to cecal cancers (11% 19/178), with a statistically significant linear trend along all subsites (P<0.0001) and little evidence of non-linearity. The proportion of F. nucleatum-low cancers was higher in rectal, ascending colon, and cecal cancers than in cancers of middle segments.

Conclusions:

The proportion of F. nucleatum-high colorectal cancers gradually increases from rectum to cecum. Our data support the colorectal continuum model that reflects pathogenic influences of the gut microbiota on neoplastic and immune cells and challenges the prevailing two-colon (proximal vs. distal) dichotomy paradigm.

Characterization of the Hispanic or latino population in health research: a systematic review

The size and diversity of the Hispanic population in the United States has dramatically increased, with vast implications for health research. We conducted a systematic review of the characterization of the Hispanic population in health research and described its implications. Relevant studies were identified by searches of PubMed, Embase Scopus, and Science/Social Sciences Citation Index from 2000 to 2011. 131 articles met criteria. 56% of the articles reported only "Hispanic" or "Latino" as the characteristic of the Hispanic research population while no other characteristics were reported. 29% of the articles reported language, 27% detailed country of origin and 2% provided the breakdown of race. There is great inconsistency in reported characteristics of Hispanics in health research. The lack of detailed characterization of this population ultimately creates roadblocks in translating evidence into practice when providing care to the large and increasingly diverse Hispanic population in the US.

MicroRNA target prediction: theory and practice

The present study is one of the few that includes tissue samples in the evaluation of target prediction algorithms designed to detect microRNA (miRNA) sequences that might interact with particular messenger RNA (mRNA) sequences. Twelve different target prediction tools were used to find miRNA sequences that might interact with CCL20 gene expression. Different algorithms predicted controversial miRNA sequences for CCL20 regulation due to a different weighting of parameters. Hsa-miR-21 and hsa-miR-145 suggested by four or more programs were chosen for further investigation. Possible real interaction of these miRNA sequences with CCL20 gene expression was monitored using luciferase assays and expression analyses of tissue samples of colorectal adenocarcinoma by either qRT-PCR or ELISA. Folding status of seed-binding sites in complete mRNA and 3'UTR of CCL20 was predicted. Prediction of miRNA expression was attempted based on CCL20 expression data. Eight of the target prediction tools forecasted a role for hsa-miR-21 and four mentioned hsa-miR-145 in CCL20 gene regulation. Laboratory experimentation showed that CCL20 may serve as a target of hsa-miR-21 but not hsa-miR-145. Expression of the molecules resulted in no clear assertion. Folding of seed-binding sites was predicted to be relatively constant for the complete mRNA and 3'UTR. Predicting miRNA expression based on target gene expression was impossible. This might be attributable to the fact that effects of miRNA activity may oscillate between gene product repression and activation. Additional systematic studies are needed to address this issue.

Resident knowledge of colorectal cancer screening assessed by web-based survey

Background

To evaluate resident knowledge of colorectal cancer (CRC) screening guidelines and to define areas requiring attention.

Methods

A survey was created using three published guidelines for CRC screening. Program directors for internal medicine residency programs were contacted within the metro New York City area to have their residents participate.

Results

Five programs participated, and 115 responses were recorded. For the appropriate testing and interval to screen for CRC, 61/115 residents identified flexible sigmoidoscopy every 5 years, 108/115 identified colonoscopy every 10 years, 16/115 identified double contrast barium enema (DCBE) every 5 years and only 12/115 thought CT-colography every 5 years was appropriate. Only 40/115 respondents appropriately identified fecal occult blood testing (FOBT) administered in the patient’s home annually, while fecal immunohistochemical testing (FIT) annually at home was identified by 8/115 residents.

Conclusion

While most residents seem knowledgeable regarding CRC screening with colonoscopy, many deficiencies remain. FOBT for screening purposes remains undervalued, and confusion about administering the test persists. The distinction between screening and prevention needs further reinforcement.

Using race as a case-mix adjustment factor in a renal dialysis payment system: potential and pitfalls

BACKGROUND

Racial disparities in health care are widespread in the United States. Identifying contributing factors may improve care for underserved minorities. To the extent that differential utilization of services, based on need or biological effect, contributes to outcome disparities, prospective payment systems may require inclusion of race to minimize these adverse effects. This research determines whether costs associated with end-stage renal disease (ESRD) care varied by race and whether this variance affected payments to dialysis facilities.

STUDY DESIGN

We compared the classification of race across Medicare databases and investigated differences in cost of care for long-term dialysis patients by race.

SETTING & PARTICIPANTS

Medicare ESRD database including 890,776 patient-years in 2004-2006.

PREDICTORS

Patient race and ethnicity.

OUTCOMES

Costs associated with ESRD care and estimated payments to dialysis facilities under a prospective payment system.

RESULTS

There were inconsistencies in race and ethnicity classification; however, there was significant agreement for classification of black and nonblack race across databases. In predictive models evaluating the cost of outpatient dialysis care for Medicare patients, race is a significant predictor of cost, particularly for cost of separately billed injectable medications used in dialysis. Overall, black patients had 9% higher costs than nonblack patients. In a model that did not adjust for race, other patient characteristics accounted for only 31% of this difference.

LIMITATIONS

Lack of information about biological causes of the link between race and cost.

CONCLUSIONS

There is a significant racial difference in the cost of providing dialysis care that is not accounted for by other factors that may be used to adjust payments. This difference has the potential to affect the delivery of care to certain populations. Of note, inclusion of race into a prospective payment system will require better understanding of biological differences in bone and anemia outcomes, as well as effects of inclusion on self-reported race.

Proximal tumors are associated with greater mortality in colon cancer

BACKGROUND

Colon cancer is the third leading cause of death from cancer in the United States. Recent studies report on increasing proportions of proximal cancers. The etiology behind this epidemiological trend is unclear, and its implication on survival outcomes is unknown. Further analysis of the impact of anatomic site of disease among a large multiethnic population will help facilitate research and education to improve colon cancer screening and treatment.

OBJECTIVE

To investigate the association between proximal tumor location and survival in patients with colon cancer.

DESIGN AND PARTICIPANTS

A large retrospective cohort study in the US utilizing the Surveillance, Epidemiology, and End Results (SEER) cancer registry analyzed survival outcomes of patients with colon cancer. Multivariable logistic regression analyses investigated sex-specific, race/ethnicity-specific, and anatomic site-specific disparities in survival.

MAIN MEASURES

Five-year survival outcomes from colon cancer.

RESULTS

Our study demonstrated significant disparities in survival by sex, race/ethnicity, and anatomic site. Across all time periods and among most cohorts, patients with proximal cancers had significantly worse survival outcomes. When compared to distal cancers, patients with proximal cancers were 13% less likely to survive 5 years (OR 0.87; 95% CI, 0.82-0.91). When compared to non-Hispanic whites, blacks were 30% less likely to survive 5 years (OR 0.70; 95% CI, 0.68-0.73). Stage-specific multivariable regression analysis of localized cancers demonstrated similar findings.

CONCLUSIONS

Significant race-specific, sex-specific, and anatomic site-specific disparities in colon cancer survival exist. Proximal cancers are associated with worse survival odds. These disparities may reflect differences in the genotype and phenotype of colon cancer among these groups. A modified risk assessment tool that incorporates these variations may be more effective in the early detection and treatment of colon cancer.